2 * IDE ATAPI streaming tape driver.
4 * Copyright (C) 1995-1999 Gadi Oxman <gadio@netvision.net.il>
5 * Copyright (C) 2003-2005 Bartlomiej Zolnierkiewicz
7 * This driver was constructed as a student project in the software laboratory
8 * of the faculty of electrical engineering in the Technion - Israel's
9 * Institute Of Technology, with the guide of Avner Lottem and Dr. Ilana David.
11 * It is hereby placed under the terms of the GNU general public license.
12 * (See linux/COPYING).
14 * For a historical changelog see
15 * Documentation/ide/ChangeLog.ide-tape.1995-2002
18 #define IDETAPE_VERSION "1.20"
20 #include <linux/module.h>
21 #include <linux/types.h>
22 #include <linux/string.h>
23 #include <linux/kernel.h>
24 #include <linux/delay.h>
25 #include <linux/timer.h>
27 #include <linux/interrupt.h>
28 #include <linux/jiffies.h>
29 #include <linux/major.h>
30 #include <linux/errno.h>
31 #include <linux/genhd.h>
32 #include <linux/slab.h>
33 #include <linux/pci.h>
34 #include <linux/ide.h>
35 #include <linux/smp_lock.h>
36 #include <linux/completion.h>
37 #include <linux/bitops.h>
38 #include <linux/mutex.h>
39 #include <scsi/scsi.h>
41 #include <asm/byteorder.h>
42 #include <linux/irq.h>
43 #include <linux/uaccess.h>
45 #include <asm/unaligned.h>
46 #include <linux/mtio.h>
49 /* output errors only */
51 /* output all sense key/asc */
53 /* info regarding all chrdev-related procedures */
54 DBG_CHRDEV = (1 << 2),
55 /* all remaining procedures */
57 /* buffer alloc info (pc_stack & rq_stack) */
58 DBG_PCRQ_STACK = (1 << 4),
61 /* define to see debug info */
62 #define IDETAPE_DEBUG_LOG 0
65 #define debug_log(lvl, fmt, args...) \
67 if (tape->debug_mask & lvl) \
68 printk(KERN_INFO "ide-tape: " fmt, ## args); \
71 #define debug_log(lvl, fmt, args...) do {} while (0)
74 /**************************** Tunable parameters *****************************/
76 * After each failed packet command we issue a request sense command and retry
77 * the packet command IDETAPE_MAX_PC_RETRIES times.
79 * Setting IDETAPE_MAX_PC_RETRIES to 0 will disable retries.
81 #define IDETAPE_MAX_PC_RETRIES 3
84 * With each packet command, we allocate a buffer of IDETAPE_PC_BUFFER_SIZE
85 * bytes. This is used for several packet commands (Not for READ/WRITE commands)
87 #define IDETAPE_PC_BUFFER_SIZE 256
90 * In various places in the driver, we need to allocate storage
91 * for packet commands and requests, which will remain valid while
92 * we leave the driver to wait for an interrupt or a timeout event.
94 #define IDETAPE_PC_STACK (10 + IDETAPE_MAX_PC_RETRIES)
97 * Some drives (for example, Seagate STT3401A Travan) require a very long
98 * timeout, because they don't return an interrupt or clear their busy bit
99 * until after the command completes (even retension commands).
101 #define IDETAPE_WAIT_CMD (900*HZ)
104 * The following parameter is used to select the point in the internal tape fifo
105 * in which we will start to refill the buffer. Decreasing the following
106 * parameter will improve the system's latency and interactive response, while
107 * using a high value might improve system throughput.
109 #define IDETAPE_FIFO_THRESHOLD 2
112 * DSC polling parameters.
114 * Polling for DSC (a single bit in the status register) is a very important
115 * function in ide-tape. There are two cases in which we poll for DSC:
117 * 1. Before a read/write packet command, to ensure that we can transfer data
118 * from/to the tape's data buffers, without causing an actual media access.
119 * In case the tape is not ready yet, we take out our request from the device
120 * request queue, so that ide.c could service requests from the other device
121 * on the same interface in the meantime.
123 * 2. After the successful initialization of a "media access packet command",
124 * which is a command that can take a long time to complete (the interval can
125 * range from several seconds to even an hour). Again, we postpone our request
126 * in the middle to free the bus for the other device. The polling frequency
127 * here should be lower than the read/write frequency since those media access
128 * commands are slow. We start from a "fast" frequency - IDETAPE_DSC_MA_FAST
129 * (1 second), and if we don't receive DSC after IDETAPE_DSC_MA_THRESHOLD
130 * (5 min), we switch it to a lower frequency - IDETAPE_DSC_MA_SLOW (1 min).
132 * We also set a timeout for the timer, in case something goes wrong. The
133 * timeout should be longer then the maximum execution time of a tape operation.
137 #define IDETAPE_DSC_RW_MIN 5*HZ/100 /* 50 msec */
138 #define IDETAPE_DSC_RW_MAX 40*HZ/100 /* 400 msec */
139 #define IDETAPE_DSC_RW_TIMEOUT 2*60*HZ /* 2 minutes */
140 #define IDETAPE_DSC_MA_FAST 2*HZ /* 2 seconds */
141 #define IDETAPE_DSC_MA_THRESHOLD 5*60*HZ /* 5 minutes */
142 #define IDETAPE_DSC_MA_SLOW 30*HZ /* 30 seconds */
143 #define IDETAPE_DSC_MA_TIMEOUT 2*60*60*HZ /* 2 hours */
145 /*************************** End of tunable parameters ***********************/
147 /* tape directions */
149 IDETAPE_DIR_NONE = (1 << 0),
150 IDETAPE_DIR_READ = (1 << 1),
151 IDETAPE_DIR_WRITE = (1 << 2),
157 struct idetape_bh *b_reqnext;
161 /* Tape door status */
162 #define DOOR_UNLOCKED 0
163 #define DOOR_LOCKED 1
164 #define DOOR_EXPLICITLY_LOCKED 2
166 /* Some defines for the SPACE command */
167 #define IDETAPE_SPACE_OVER_FILEMARK 1
168 #define IDETAPE_SPACE_TO_EOD 3
170 /* Some defines for the LOAD UNLOAD command */
171 #define IDETAPE_LU_LOAD_MASK 1
172 #define IDETAPE_LU_RETENSION_MASK 2
173 #define IDETAPE_LU_EOT_MASK 4
176 * Special requests for our block device strategy routine.
178 * In order to service a character device command, we add special requests to
179 * the tail of our block device request queue and wait for their completion.
183 REQ_IDETAPE_PC1 = (1 << 0), /* packet command (first stage) */
184 REQ_IDETAPE_PC2 = (1 << 1), /* packet command (second stage) */
185 REQ_IDETAPE_READ = (1 << 2),
186 REQ_IDETAPE_WRITE = (1 << 3),
189 /* Error codes returned in rq->errors to the higher part of the driver. */
190 #define IDETAPE_ERROR_GENERAL 101
191 #define IDETAPE_ERROR_FILEMARK 102
192 #define IDETAPE_ERROR_EOD 103
194 /* Structures related to the SELECT SENSE / MODE SENSE packet commands. */
195 #define IDETAPE_BLOCK_DESCRIPTOR 0
196 #define IDETAPE_CAPABILITIES_PAGE 0x2a
198 /* Tape flag bits values. */
200 IDETAPE_FLAG_IGNORE_DSC = (1 << 0),
201 /* 0 When the tape position is unknown */
202 IDETAPE_FLAG_ADDRESS_VALID = (1 << 1),
203 /* Device already opened */
204 IDETAPE_FLAG_BUSY = (1 << 2),
205 /* Attempt to auto-detect the current user block size */
206 IDETAPE_FLAG_DETECT_BS = (1 << 3),
207 /* Currently on a filemark */
208 IDETAPE_FLAG_FILEMARK = (1 << 4),
209 /* DRQ interrupt device */
210 IDETAPE_FLAG_DRQ_INTERRUPT = (1 << 5),
211 /* 0 = no tape is loaded, so we don't rewind after ejecting */
212 IDETAPE_FLAG_MEDIUM_PRESENT = (1 << 6),
216 * Most of our global data which we need to save even as we leave the driver due
217 * to an interrupt or a timer event is stored in the struct defined below.
219 typedef struct ide_tape_obj {
221 ide_driver_t *driver;
222 struct gendisk *disk;
226 * Since a typical character device operation requires more
227 * than one packet command, we provide here enough memory
228 * for the maximum of interconnected packet commands.
229 * The packet commands are stored in the circular array pc_stack.
230 * pc_stack_index points to the last used entry, and warps around
231 * to the start when we get to the last array entry.
233 * pc points to the current processed packet command.
235 * failed_pc points to the last failed packet command, or contains
236 * NULL if we do not need to retry any packet command. This is
237 * required since an additional packet command is needed before the
238 * retry, to get detailed information on what went wrong.
240 /* Current packet command */
241 struct ide_atapi_pc *pc;
242 /* Last failed packet command */
243 struct ide_atapi_pc *failed_pc;
244 /* Packet command stack */
245 struct ide_atapi_pc pc_stack[IDETAPE_PC_STACK];
246 /* Next free packet command storage space */
248 struct request rq_stack[IDETAPE_PC_STACK];
249 /* We implement a circular array */
253 * DSC polling variables.
255 * While polling for DSC we use postponed_rq to postpone the current
256 * request so that ide.c will be able to service pending requests on the
257 * other device. Note that at most we will have only one DSC (usually
258 * data transfer) request in the device request queue.
260 struct request *postponed_rq;
261 /* The time in which we started polling for DSC */
262 unsigned long dsc_polling_start;
263 /* Timer used to poll for dsc */
264 struct timer_list dsc_timer;
265 /* Read/Write dsc polling frequency */
266 unsigned long best_dsc_rw_freq;
267 unsigned long dsc_poll_freq;
268 unsigned long dsc_timeout;
270 /* Read position information */
273 unsigned int first_frame;
275 /* Last error information */
276 u8 sense_key, asc, ascq;
278 /* Character device operation */
282 /* Current character device data transfer direction */
285 /* tape block size, usually 512 or 1024 bytes */
286 unsigned short blk_size;
289 /* Copy of the tape's Capabilities and Mechanical Page */
293 * Active data transfer request parameters.
295 * At most, there is only one ide-tape originated data transfer request
296 * in the device request queue. This allows ide.c to easily service
297 * requests from the other device when we postpone our active request.
300 /* Data buffer size chosen based on the tape's recommendation */
303 struct idetape_bh *merge_bh;
304 /* size of the merge buffer */
306 /* pointer to current buffer head within the merge buffer */
307 struct idetape_bh *bh;
311 int pages_per_buffer;
312 /* Wasted space in each stage */
315 /* Status/Action flags: long for set_bit */
317 /* protects the ide-tape queue */
320 /* Measures average tape speed */
321 unsigned long avg_time;
325 /* the door is currently locked */
327 /* the tape hardware is write protected */
329 /* the tape is write protected (hardware or opened as read-only) */
335 static DEFINE_MUTEX(idetape_ref_mutex);
337 static struct class *idetape_sysfs_class;
339 #define to_ide_tape(obj) container_of(obj, struct ide_tape_obj, kref)
341 #define ide_tape_g(disk) \
342 container_of((disk)->private_data, struct ide_tape_obj, driver)
344 static struct ide_tape_obj *ide_tape_get(struct gendisk *disk)
346 struct ide_tape_obj *tape = NULL;
348 mutex_lock(&idetape_ref_mutex);
349 tape = ide_tape_g(disk);
351 kref_get(&tape->kref);
352 mutex_unlock(&idetape_ref_mutex);
356 static void ide_tape_release(struct kref *);
358 static void ide_tape_put(struct ide_tape_obj *tape)
360 mutex_lock(&idetape_ref_mutex);
361 kref_put(&tape->kref, ide_tape_release);
362 mutex_unlock(&idetape_ref_mutex);
366 * The variables below are used for the character device interface. Additional
367 * state variables are defined in our ide_drive_t structure.
369 static struct ide_tape_obj *idetape_devs[MAX_HWIFS * MAX_DRIVES];
371 #define ide_tape_f(file) ((file)->private_data)
373 static struct ide_tape_obj *ide_tape_chrdev_get(unsigned int i)
375 struct ide_tape_obj *tape = NULL;
377 mutex_lock(&idetape_ref_mutex);
378 tape = idetape_devs[i];
380 kref_get(&tape->kref);
381 mutex_unlock(&idetape_ref_mutex);
385 static void idetape_input_buffers(ide_drive_t *drive, struct ide_atapi_pc *pc,
388 struct idetape_bh *bh = pc->bh;
393 printk(KERN_ERR "ide-tape: bh == NULL in "
394 "idetape_input_buffers\n");
395 ide_pad_transfer(drive, 0, bcount);
399 (unsigned int)(bh->b_size - atomic_read(&bh->b_count)),
401 drive->hwif->input_data(drive, NULL, bh->b_data +
402 atomic_read(&bh->b_count), count);
404 atomic_add(count, &bh->b_count);
405 if (atomic_read(&bh->b_count) == bh->b_size) {
408 atomic_set(&bh->b_count, 0);
414 static void idetape_output_buffers(ide_drive_t *drive, struct ide_atapi_pc *pc,
417 struct idetape_bh *bh = pc->bh;
422 printk(KERN_ERR "ide-tape: bh == NULL in %s\n",
426 count = min((unsigned int)pc->b_count, (unsigned int)bcount);
427 drive->hwif->output_data(drive, NULL, pc->b_data, count);
430 pc->b_count -= count;
435 pc->b_data = bh->b_data;
436 pc->b_count = atomic_read(&bh->b_count);
442 static void idetape_update_buffers(struct ide_atapi_pc *pc)
444 struct idetape_bh *bh = pc->bh;
446 unsigned int bcount = pc->xferred;
448 if (pc->flags & PC_FLAG_WRITING)
452 printk(KERN_ERR "ide-tape: bh == NULL in %s\n",
456 count = min((unsigned int)bh->b_size, (unsigned int)bcount);
457 atomic_set(&bh->b_count, count);
458 if (atomic_read(&bh->b_count) == bh->b_size)
466 * idetape_next_pc_storage returns a pointer to a place in which we can
467 * safely store a packet command, even though we intend to leave the
468 * driver. A storage space for a maximum of IDETAPE_PC_STACK packet
469 * commands is allocated at initialization time.
471 static struct ide_atapi_pc *idetape_next_pc_storage(ide_drive_t *drive)
473 idetape_tape_t *tape = drive->driver_data;
475 debug_log(DBG_PCRQ_STACK, "pc_stack_index=%d\n", tape->pc_stack_index);
477 if (tape->pc_stack_index == IDETAPE_PC_STACK)
478 tape->pc_stack_index = 0;
479 return (&tape->pc_stack[tape->pc_stack_index++]);
483 * idetape_next_rq_storage is used along with idetape_next_pc_storage.
484 * Since we queue packet commands in the request queue, we need to
485 * allocate a request, along with the allocation of a packet command.
488 /**************************************************************
490 * This should get fixed to use kmalloc(.., GFP_ATOMIC) *
491 * followed later on by kfree(). -ml *
493 **************************************************************/
495 static struct request *idetape_next_rq_storage(ide_drive_t *drive)
497 idetape_tape_t *tape = drive->driver_data;
499 debug_log(DBG_PCRQ_STACK, "rq_stack_index=%d\n", tape->rq_stack_index);
501 if (tape->rq_stack_index == IDETAPE_PC_STACK)
502 tape->rq_stack_index = 0;
503 return (&tape->rq_stack[tape->rq_stack_index++]);
507 * called on each failed packet command retry to analyze the request sense. We
508 * currently do not utilize this information.
510 static void idetape_analyze_error(ide_drive_t *drive, u8 *sense)
512 idetape_tape_t *tape = drive->driver_data;
513 struct ide_atapi_pc *pc = tape->failed_pc;
515 tape->sense_key = sense[2] & 0xF;
516 tape->asc = sense[12];
517 tape->ascq = sense[13];
519 debug_log(DBG_ERR, "pc = %x, sense key = %x, asc = %x, ascq = %x\n",
520 pc->c[0], tape->sense_key, tape->asc, tape->ascq);
522 /* Correct pc->xferred by asking the tape. */
523 if (pc->flags & PC_FLAG_DMA_ERROR) {
524 pc->xferred = pc->req_xfer -
526 get_unaligned_be32(&sense[3]);
527 idetape_update_buffers(pc);
531 * If error was the result of a zero-length read or write command,
532 * with sense key=5, asc=0x22, ascq=0, let it slide. Some drives
533 * (i.e. Seagate STT3401A Travan) don't support 0-length read/writes.
535 if ((pc->c[0] == READ_6 || pc->c[0] == WRITE_6)
537 && pc->c[4] == 0 && pc->c[3] == 0 && pc->c[2] == 0) {
538 if (tape->sense_key == 5) {
539 /* don't report an error, everything's ok */
541 /* don't retry read/write */
542 pc->flags |= PC_FLAG_ABORT;
545 if (pc->c[0] == READ_6 && (sense[2] & 0x80)) {
546 pc->error = IDETAPE_ERROR_FILEMARK;
547 pc->flags |= PC_FLAG_ABORT;
549 if (pc->c[0] == WRITE_6) {
550 if ((sense[2] & 0x40) || (tape->sense_key == 0xd
551 && tape->asc == 0x0 && tape->ascq == 0x2)) {
552 pc->error = IDETAPE_ERROR_EOD;
553 pc->flags |= PC_FLAG_ABORT;
556 if (pc->c[0] == READ_6 || pc->c[0] == WRITE_6) {
557 if (tape->sense_key == 8) {
558 pc->error = IDETAPE_ERROR_EOD;
559 pc->flags |= PC_FLAG_ABORT;
561 if (!(pc->flags & PC_FLAG_ABORT) &&
563 pc->retries = IDETAPE_MAX_PC_RETRIES + 1;
567 /* Free data buffers completely. */
568 static void ide_tape_kfree_buffer(idetape_tape_t *tape)
570 struct idetape_bh *prev_bh, *bh = tape->merge_bh;
573 u32 size = bh->b_size;
576 unsigned int order = fls(size >> PAGE_SHIFT)-1;
579 free_pages((unsigned long)bh->b_data, order);
582 bh->b_data += (1 << order) * PAGE_SIZE;
588 kfree(tape->merge_bh);
591 static int idetape_end_request(ide_drive_t *drive, int uptodate, int nr_sects)
593 struct request *rq = HWGROUP(drive)->rq;
594 idetape_tape_t *tape = drive->driver_data;
598 debug_log(DBG_PROCS, "Enter %s\n", __func__);
601 case 0: error = IDETAPE_ERROR_GENERAL; break;
602 case 1: error = 0; break;
603 default: error = uptodate;
607 tape->failed_pc = NULL;
609 if (!blk_special_request(rq)) {
610 ide_end_request(drive, uptodate, nr_sects);
614 spin_lock_irqsave(&tape->lock, flags);
616 ide_end_drive_cmd(drive, 0, 0);
618 spin_unlock_irqrestore(&tape->lock, flags);
622 static ide_startstop_t ide_tape_callback(ide_drive_t *drive)
624 idetape_tape_t *tape = drive->driver_data;
625 struct ide_atapi_pc *pc = tape->pc;
626 int uptodate = pc->error ? 0 : 1;
628 debug_log(DBG_PROCS, "Enter %s\n", __func__);
630 if (pc->c[0] == REQUEST_SENSE) {
632 idetape_analyze_error(drive, pc->buf);
634 printk(KERN_ERR "ide-tape: Error in REQUEST SENSE "
635 "itself - Aborting request!\n");
636 } else if (pc->c[0] == READ_6 || pc->c[0] == WRITE_6) {
637 struct request *rq = drive->hwif->hwgroup->rq;
638 int blocks = pc->xferred / tape->blk_size;
640 tape->avg_size += blocks * tape->blk_size;
642 if (time_after_eq(jiffies, tape->avg_time + HZ)) {
643 tape->avg_speed = tape->avg_size * HZ /
644 (jiffies - tape->avg_time) / 1024;
646 tape->avg_time = jiffies;
649 tape->first_frame += blocks;
650 rq->current_nr_sectors -= blocks;
653 uptodate = pc->error;
654 } else if (pc->c[0] == READ_POSITION && uptodate) {
655 u8 *readpos = tape->pc->buf;
657 debug_log(DBG_SENSE, "BOP - %s\n",
658 (readpos[0] & 0x80) ? "Yes" : "No");
659 debug_log(DBG_SENSE, "EOP - %s\n",
660 (readpos[0] & 0x40) ? "Yes" : "No");
662 if (readpos[0] & 0x4) {
663 printk(KERN_INFO "ide-tape: Block location is unknown"
665 clear_bit(IDETAPE_FLAG_ADDRESS_VALID, &tape->flags);
668 debug_log(DBG_SENSE, "Block Location - %u\n",
669 be32_to_cpu(*(u32 *)&readpos[4]));
671 tape->partition = readpos[1];
672 tape->first_frame = be32_to_cpu(*(u32 *)&readpos[4]);
673 set_bit(IDETAPE_FLAG_ADDRESS_VALID, &tape->flags);
677 idetape_end_request(drive, uptodate, 0);
682 static void idetape_init_pc(struct ide_atapi_pc *pc)
684 memset(pc->c, 0, 12);
688 pc->buf = pc->pc_buf;
689 pc->buf_size = IDETAPE_PC_BUFFER_SIZE;
692 pc->idetape_callback = ide_tape_callback;
695 static void idetape_create_request_sense_cmd(struct ide_atapi_pc *pc)
698 pc->c[0] = REQUEST_SENSE;
703 static void idetape_init_rq(struct request *rq, u8 cmd)
705 blk_rq_init(NULL, rq);
706 rq->cmd_type = REQ_TYPE_SPECIAL;
711 * Generate a new packet command request in front of the request queue, before
712 * the current request, so that it will be processed immediately, on the next
713 * pass through the driver. The function below is called from the request
714 * handling part of the driver (the "bottom" part). Safe storage for the request
715 * should be allocated with ide_tape_next_{pc,rq}_storage() prior to that.
717 * Memory for those requests is pre-allocated at initialization time, and is
718 * limited to IDETAPE_PC_STACK requests. We assume that we have enough space for
719 * the maximum possible number of inter-dependent packet commands.
721 * The higher level of the driver - The ioctl handler and the character device
722 * handling functions should queue request to the lower level part and wait for
723 * their completion using idetape_queue_pc_tail or idetape_queue_rw_tail.
725 static void idetape_queue_pc_head(ide_drive_t *drive, struct ide_atapi_pc *pc,
728 struct ide_tape_obj *tape = drive->driver_data;
730 idetape_init_rq(rq, REQ_IDETAPE_PC1);
731 rq->cmd_flags |= REQ_PREEMPT;
732 rq->buffer = (char *) pc;
733 rq->rq_disk = tape->disk;
734 ide_do_drive_cmd(drive, rq);
738 * idetape_retry_pc is called when an error was detected during the
739 * last packet command. We queue a request sense packet command in
740 * the head of the request list.
742 static void idetape_retry_pc(ide_drive_t *drive)
744 idetape_tape_t *tape = drive->driver_data;
745 struct ide_atapi_pc *pc;
748 (void)ide_read_error(drive);
749 pc = idetape_next_pc_storage(drive);
750 rq = idetape_next_rq_storage(drive);
751 idetape_create_request_sense_cmd(pc);
752 set_bit(IDETAPE_FLAG_IGNORE_DSC, &tape->flags);
753 idetape_queue_pc_head(drive, pc, rq);
757 * Postpone the current request so that ide.c will be able to service requests
758 * from another device on the same hwgroup while we are polling for DSC.
760 static void idetape_postpone_request(ide_drive_t *drive)
762 idetape_tape_t *tape = drive->driver_data;
764 debug_log(DBG_PROCS, "Enter %s\n", __func__);
766 tape->postponed_rq = HWGROUP(drive)->rq;
767 ide_stall_queue(drive, tape->dsc_poll_freq);
770 typedef void idetape_io_buf(ide_drive_t *, struct ide_atapi_pc *, unsigned int);
773 * This is the usual interrupt handler which will be called during a packet
774 * command. We will transfer some of the data (as requested by the drive) and
775 * will re-point interrupt handler to us. When data transfer is finished, we
776 * will act according to the algorithm described before
779 static ide_startstop_t idetape_pc_intr(ide_drive_t *drive)
781 ide_hwif_t *hwif = drive->hwif;
782 idetape_tape_t *tape = drive->driver_data;
783 struct ide_atapi_pc *pc = tape->pc;
784 xfer_func_t *xferfunc;
785 idetape_io_buf *iobuf;
790 debug_log(DBG_PROCS, "Enter %s - interrupt handler\n", __func__);
792 /* Clear the interrupt */
793 stat = ide_read_status(drive);
795 if (pc->flags & PC_FLAG_DMA_IN_PROGRESS) {
796 if (hwif->dma_ops->dma_end(drive) || (stat & ERR_STAT)) {
797 pc->flags |= PC_FLAG_DMA_ERROR;
799 pc->xferred = pc->req_xfer;
800 idetape_update_buffers(pc);
802 debug_log(DBG_PROCS, "DMA finished\n");
806 /* No more interrupts */
807 if ((stat & DRQ_STAT) == 0) {
808 debug_log(DBG_SENSE, "Packet command completed, %d bytes"
809 " transferred\n", pc->xferred);
811 pc->flags &= ~PC_FLAG_DMA_IN_PROGRESS;
812 local_irq_enable_in_hardirq();
814 if ((stat & ERR_STAT) && pc->c[0] == REQUEST_SENSE)
816 if ((stat & ERR_STAT) || (pc->flags & PC_FLAG_DMA_ERROR)) {
818 debug_log(DBG_ERR, "%s: I/O error\n", tape->name);
820 if (pc->c[0] == REQUEST_SENSE) {
821 printk(KERN_ERR "%s: I/O error in request sense"
822 " command\n", drive->name);
823 return ide_do_reset(drive);
825 debug_log(DBG_ERR, "[cmd %x]: check condition\n",
828 /* Retry operation */
829 idetape_retry_pc(drive);
833 if ((pc->flags & PC_FLAG_WAIT_FOR_DSC) &&
834 (stat & SEEK_STAT) == 0) {
835 /* Media access command */
836 tape->dsc_polling_start = jiffies;
837 tape->dsc_poll_freq = IDETAPE_DSC_MA_FAST;
838 tape->dsc_timeout = jiffies + IDETAPE_DSC_MA_TIMEOUT;
839 /* Allow ide.c to handle other requests */
840 idetape_postpone_request(drive);
843 if (tape->failed_pc == pc)
844 tape->failed_pc = NULL;
845 /* Command finished - Call the callback function */
846 return pc->idetape_callback(drive);
849 if (pc->flags & PC_FLAG_DMA_IN_PROGRESS) {
850 pc->flags &= ~PC_FLAG_DMA_IN_PROGRESS;
851 printk(KERN_ERR "%s: The device wants to issue more interrupts "
852 "in DMA mode\n", drive->name);
854 return ide_do_reset(drive);
856 /* Get the number of bytes to transfer on this interrupt. */
857 bcount = (hwif->INB(hwif->io_ports.lbah_addr) << 8) |
858 hwif->INB(hwif->io_ports.lbam_addr);
860 ireason = hwif->INB(hwif->io_ports.nsect_addr);
863 printk(KERN_ERR "%s: CoD != 0 in %s\n", drive->name, __func__);
864 return ide_do_reset(drive);
866 if (((ireason & IO) == IO) == !!(pc->flags & PC_FLAG_WRITING)) {
867 /* Hopefully, we will never get here */
868 printk(KERN_ERR "%s: We wanted to %s, but the device wants us "
869 "to %s!\n", drive->name,
870 (ireason & IO) ? "Write" : "Read",
871 (ireason & IO) ? "Read" : "Write");
872 return ide_do_reset(drive);
874 if (!(pc->flags & PC_FLAG_WRITING)) {
875 /* Reading - Check that we have enough space */
876 temp = pc->xferred + bcount;
877 if (temp > pc->req_xfer) {
878 if (temp > pc->buf_size) {
879 printk(KERN_ERR "%s: The device wants to send "
880 "us more data than expected - "
883 ide_pad_transfer(drive, 0, bcount);
884 ide_set_handler(drive, &idetape_pc_intr,
885 IDETAPE_WAIT_CMD, NULL);
888 debug_log(DBG_SENSE, "The device wants to send us more "
889 "data than expected - allowing transfer\n");
891 iobuf = &idetape_input_buffers;
892 xferfunc = hwif->input_data;
894 iobuf = &idetape_output_buffers;
895 xferfunc = hwif->output_data;
899 iobuf(drive, pc, bcount);
901 xferfunc(drive, NULL, pc->cur_pos, bcount);
903 /* Update the current position */
904 pc->xferred += bcount;
905 pc->cur_pos += bcount;
907 debug_log(DBG_SENSE, "[cmd %x] transferred %d bytes on that intr.\n",
910 /* And set the interrupt handler again */
911 ide_set_handler(drive, &idetape_pc_intr, IDETAPE_WAIT_CMD, NULL);
916 * Packet Command Interface
918 * The current Packet Command is available in tape->pc, and will not change
919 * until we finish handling it. Each packet command is associated with a
920 * callback function that will be called when the command is finished.
922 * The handling will be done in three stages:
924 * 1. idetape_issue_pc will send the packet command to the drive, and will set
925 * the interrupt handler to idetape_pc_intr.
927 * 2. On each interrupt, idetape_pc_intr will be called. This step will be
928 * repeated until the device signals us that no more interrupts will be issued.
930 * 3. ATAPI Tape media access commands have immediate status with a delayed
931 * process. In case of a successful initiation of a media access packet command,
932 * the DSC bit will be set when the actual execution of the command is finished.
933 * Since the tape drive will not issue an interrupt, we have to poll for this
934 * event. In this case, we define the request as "low priority request" by
935 * setting rq_status to IDETAPE_RQ_POSTPONED, set a timer to poll for DSC and
938 * ide.c will then give higher priority to requests which originate from the
939 * other device, until will change rq_status to RQ_ACTIVE.
941 * 4. When the packet command is finished, it will be checked for errors.
943 * 5. In case an error was found, we queue a request sense packet command in
944 * front of the request queue and retry the operation up to
945 * IDETAPE_MAX_PC_RETRIES times.
947 * 6. In case no error was found, or we decided to give up and not to retry
948 * again, the callback function will be called and then we will handle the next
951 static ide_startstop_t idetape_transfer_pc(ide_drive_t *drive)
953 ide_hwif_t *hwif = drive->hwif;
954 idetape_tape_t *tape = drive->driver_data;
955 struct ide_atapi_pc *pc = tape->pc;
957 ide_startstop_t startstop;
960 if (ide_wait_stat(&startstop, drive, DRQ_STAT, BUSY_STAT, WAIT_READY)) {
961 printk(KERN_ERR "%s: Strange, packet command initiated yet "
962 "DRQ isn't asserted\n", drive->name);
965 ireason = hwif->INB(hwif->io_ports.nsect_addr);
966 while (retries-- && ((ireason & CD) == 0 || (ireason & IO))) {
967 printk(KERN_ERR "%s: (IO,CoD != (0,1) while issuing "
968 "a packet command, retrying\n", drive->name);
970 ireason = hwif->INB(hwif->io_ports.nsect_addr);
972 printk(KERN_ERR "%s: (IO,CoD != (0,1) while issuing "
973 "a packet command, ignoring\n",
979 if ((ireason & CD) == 0 || (ireason & IO)) {
980 printk(KERN_ERR "%s: (IO,CoD) != (0,1) while issuing "
981 "a packet command\n", drive->name);
982 return ide_do_reset(drive);
984 /* Set the interrupt routine */
985 ide_set_handler(drive, &idetape_pc_intr, IDETAPE_WAIT_CMD, NULL);
987 /* Begin DMA, if necessary */
988 if (pc->flags & PC_FLAG_DMA_IN_PROGRESS)
989 hwif->dma_ops->dma_start(drive);
991 /* Send the actual packet */
992 hwif->output_data(drive, NULL, pc->c, 12);
997 static ide_startstop_t idetape_issue_pc(ide_drive_t *drive,
998 struct ide_atapi_pc *pc)
1000 ide_hwif_t *hwif = drive->hwif;
1001 idetape_tape_t *tape = drive->driver_data;
1005 if (tape->pc->c[0] == REQUEST_SENSE &&
1006 pc->c[0] == REQUEST_SENSE) {
1007 printk(KERN_ERR "ide-tape: possible ide-tape.c bug - "
1008 "Two request sense in serial were issued\n");
1011 if (tape->failed_pc == NULL && pc->c[0] != REQUEST_SENSE)
1012 tape->failed_pc = pc;
1013 /* Set the current packet command */
1016 if (pc->retries > IDETAPE_MAX_PC_RETRIES ||
1017 (pc->flags & PC_FLAG_ABORT)) {
1019 * We will "abort" retrying a packet command in case legitimate
1020 * error code was received (crossing a filemark, or end of the
1021 * media, for example).
1023 if (!(pc->flags & PC_FLAG_ABORT)) {
1024 if (!(pc->c[0] == TEST_UNIT_READY &&
1025 tape->sense_key == 2 && tape->asc == 4 &&
1026 (tape->ascq == 1 || tape->ascq == 8))) {
1027 printk(KERN_ERR "ide-tape: %s: I/O error, "
1028 "pc = %2x, key = %2x, "
1029 "asc = %2x, ascq = %2x\n",
1030 tape->name, pc->c[0],
1031 tape->sense_key, tape->asc,
1035 pc->error = IDETAPE_ERROR_GENERAL;
1037 tape->failed_pc = NULL;
1038 return pc->idetape_callback(drive);
1040 debug_log(DBG_SENSE, "Retry #%d, cmd = %02X\n", pc->retries, pc->c[0]);
1043 /* We haven't transferred any data yet */
1045 pc->cur_pos = pc->buf;
1046 /* Request to transfer the entire buffer at once */
1047 bcount = pc->req_xfer;
1049 if (pc->flags & PC_FLAG_DMA_ERROR) {
1050 pc->flags &= ~PC_FLAG_DMA_ERROR;
1053 if ((pc->flags & PC_FLAG_DMA_RECOMMENDED) && drive->using_dma)
1054 dma_ok = !hwif->dma_ops->dma_setup(drive);
1056 ide_pktcmd_tf_load(drive, IDE_TFLAG_OUT_DEVICE, bcount, dma_ok);
1059 /* Will begin DMA later */
1060 pc->flags |= PC_FLAG_DMA_IN_PROGRESS;
1061 if (test_bit(IDETAPE_FLAG_DRQ_INTERRUPT, &tape->flags)) {
1062 ide_execute_command(drive, WIN_PACKETCMD, &idetape_transfer_pc,
1063 IDETAPE_WAIT_CMD, NULL);
1066 ide_execute_pkt_cmd(drive);
1067 return idetape_transfer_pc(drive);
1071 /* A mode sense command is used to "sense" tape parameters. */
1072 static void idetape_create_mode_sense_cmd(struct ide_atapi_pc *pc, u8 page_code)
1074 idetape_init_pc(pc);
1075 pc->c[0] = MODE_SENSE;
1076 if (page_code != IDETAPE_BLOCK_DESCRIPTOR)
1077 /* DBD = 1 - Don't return block descriptors */
1079 pc->c[2] = page_code;
1081 * Changed pc->c[3] to 0 (255 will at best return unused info).
1083 * For SCSI this byte is defined as subpage instead of high byte
1084 * of length and some IDE drives seem to interpret it this way
1085 * and return an error when 255 is used.
1088 /* We will just discard data in that case */
1090 if (page_code == IDETAPE_BLOCK_DESCRIPTOR)
1092 else if (page_code == IDETAPE_CAPABILITIES_PAGE)
1098 static ide_startstop_t idetape_media_access_finished(ide_drive_t *drive)
1100 idetape_tape_t *tape = drive->driver_data;
1101 struct ide_atapi_pc *pc = tape->pc;
1104 stat = ide_read_status(drive);
1106 if (stat & SEEK_STAT) {
1107 if (stat & ERR_STAT) {
1108 /* Error detected */
1109 if (pc->c[0] != TEST_UNIT_READY)
1110 printk(KERN_ERR "ide-tape: %s: I/O error, ",
1112 /* Retry operation */
1113 idetape_retry_pc(drive);
1117 if (tape->failed_pc == pc)
1118 tape->failed_pc = NULL;
1120 pc->error = IDETAPE_ERROR_GENERAL;
1121 tape->failed_pc = NULL;
1123 return pc->idetape_callback(drive);
1126 static void idetape_create_read_cmd(idetape_tape_t *tape,
1127 struct ide_atapi_pc *pc,
1128 unsigned int length, struct idetape_bh *bh)
1130 idetape_init_pc(pc);
1132 put_unaligned(cpu_to_be32(length), (unsigned int *) &pc->c[1]);
1135 atomic_set(&bh->b_count, 0);
1137 pc->buf_size = length * tape->blk_size;
1138 pc->req_xfer = pc->buf_size;
1139 if (pc->req_xfer == tape->buffer_size)
1140 pc->flags |= PC_FLAG_DMA_RECOMMENDED;
1143 static void idetape_create_write_cmd(idetape_tape_t *tape,
1144 struct ide_atapi_pc *pc,
1145 unsigned int length, struct idetape_bh *bh)
1147 idetape_init_pc(pc);
1149 put_unaligned(cpu_to_be32(length), (unsigned int *) &pc->c[1]);
1151 pc->flags |= PC_FLAG_WRITING;
1153 pc->b_data = bh->b_data;
1154 pc->b_count = atomic_read(&bh->b_count);
1156 pc->buf_size = length * tape->blk_size;
1157 pc->req_xfer = pc->buf_size;
1158 if (pc->req_xfer == tape->buffer_size)
1159 pc->flags |= PC_FLAG_DMA_RECOMMENDED;
1162 static ide_startstop_t idetape_do_request(ide_drive_t *drive,
1163 struct request *rq, sector_t block)
1165 idetape_tape_t *tape = drive->driver_data;
1166 struct ide_atapi_pc *pc = NULL;
1167 struct request *postponed_rq = tape->postponed_rq;
1170 debug_log(DBG_SENSE, "sector: %ld, nr_sectors: %ld,"
1171 " current_nr_sectors: %d\n",
1172 rq->sector, rq->nr_sectors, rq->current_nr_sectors);
1174 if (!blk_special_request(rq)) {
1175 /* We do not support buffer cache originated requests. */
1176 printk(KERN_NOTICE "ide-tape: %s: Unsupported request in "
1177 "request queue (%d)\n", drive->name, rq->cmd_type);
1178 ide_end_request(drive, 0, 0);
1182 /* Retry a failed packet command */
1183 if (tape->failed_pc && tape->pc->c[0] == REQUEST_SENSE)
1184 return idetape_issue_pc(drive, tape->failed_pc);
1186 if (postponed_rq != NULL)
1187 if (rq != postponed_rq) {
1188 printk(KERN_ERR "ide-tape: ide-tape.c bug - "
1189 "Two DSC requests were queued\n");
1190 idetape_end_request(drive, 0, 0);
1194 tape->postponed_rq = NULL;
1197 * If the tape is still busy, postpone our request and service
1198 * the other device meanwhile.
1200 stat = ide_read_status(drive);
1202 if (!drive->dsc_overlap && !(rq->cmd[0] & REQ_IDETAPE_PC2))
1203 set_bit(IDETAPE_FLAG_IGNORE_DSC, &tape->flags);
1205 if (drive->post_reset == 1) {
1206 set_bit(IDETAPE_FLAG_IGNORE_DSC, &tape->flags);
1207 drive->post_reset = 0;
1210 if (!test_and_clear_bit(IDETAPE_FLAG_IGNORE_DSC, &tape->flags) &&
1211 (stat & SEEK_STAT) == 0) {
1212 if (postponed_rq == NULL) {
1213 tape->dsc_polling_start = jiffies;
1214 tape->dsc_poll_freq = tape->best_dsc_rw_freq;
1215 tape->dsc_timeout = jiffies + IDETAPE_DSC_RW_TIMEOUT;
1216 } else if (time_after(jiffies, tape->dsc_timeout)) {
1217 printk(KERN_ERR "ide-tape: %s: DSC timeout\n",
1219 if (rq->cmd[0] & REQ_IDETAPE_PC2) {
1220 idetape_media_access_finished(drive);
1223 return ide_do_reset(drive);
1225 } else if (time_after(jiffies,
1226 tape->dsc_polling_start +
1227 IDETAPE_DSC_MA_THRESHOLD))
1228 tape->dsc_poll_freq = IDETAPE_DSC_MA_SLOW;
1229 idetape_postpone_request(drive);
1232 if (rq->cmd[0] & REQ_IDETAPE_READ) {
1233 pc = idetape_next_pc_storage(drive);
1234 idetape_create_read_cmd(tape, pc, rq->current_nr_sectors,
1235 (struct idetape_bh *)rq->special);
1238 if (rq->cmd[0] & REQ_IDETAPE_WRITE) {
1239 pc = idetape_next_pc_storage(drive);
1240 idetape_create_write_cmd(tape, pc, rq->current_nr_sectors,
1241 (struct idetape_bh *)rq->special);
1244 if (rq->cmd[0] & REQ_IDETAPE_PC1) {
1245 pc = (struct ide_atapi_pc *) rq->buffer;
1246 rq->cmd[0] &= ~(REQ_IDETAPE_PC1);
1247 rq->cmd[0] |= REQ_IDETAPE_PC2;
1250 if (rq->cmd[0] & REQ_IDETAPE_PC2) {
1251 idetape_media_access_finished(drive);
1256 return idetape_issue_pc(drive, pc);
1260 * The function below uses __get_free_pages to allocate a data buffer of size
1261 * tape->buffer_size (or a bit more). We attempt to combine sequential pages as
1264 * It returns a pointer to the newly allocated buffer, or NULL in case of
1267 static struct idetape_bh *ide_tape_kmalloc_buffer(idetape_tape_t *tape,
1268 int full, int clear)
1270 struct idetape_bh *prev_bh, *bh, *merge_bh;
1271 int pages = tape->pages_per_buffer;
1272 unsigned int order, b_allocd;
1273 char *b_data = NULL;
1275 merge_bh = kmalloc(sizeof(struct idetape_bh), GFP_KERNEL);
1280 order = fls(pages) - 1;
1281 bh->b_data = (char *) __get_free_pages(GFP_KERNEL, order);
1284 b_allocd = (1 << order) * PAGE_SIZE;
1288 memset(bh->b_data, 0, b_allocd);
1289 bh->b_reqnext = NULL;
1290 bh->b_size = b_allocd;
1291 atomic_set(&bh->b_count, full ? bh->b_size : 0);
1294 order = fls(pages) - 1;
1295 b_data = (char *) __get_free_pages(GFP_KERNEL, order);
1298 b_allocd = (1 << order) * PAGE_SIZE;
1301 memset(b_data, 0, b_allocd);
1303 /* newly allocated page frames below buffer header or ...*/
1304 if (bh->b_data == b_data + b_allocd) {
1305 bh->b_size += b_allocd;
1306 bh->b_data -= b_allocd;
1308 atomic_add(b_allocd, &bh->b_count);
1311 /* they are above the header */
1312 if (b_data == bh->b_data + bh->b_size) {
1313 bh->b_size += b_allocd;
1315 atomic_add(b_allocd, &bh->b_count);
1319 bh = kmalloc(sizeof(struct idetape_bh), GFP_KERNEL);
1321 free_pages((unsigned long) b_data, order);
1324 bh->b_reqnext = NULL;
1325 bh->b_data = b_data;
1326 bh->b_size = b_allocd;
1327 atomic_set(&bh->b_count, full ? bh->b_size : 0);
1328 prev_bh->b_reqnext = bh;
1333 bh->b_size -= tape->excess_bh_size;
1335 atomic_sub(tape->excess_bh_size, &bh->b_count);
1338 ide_tape_kfree_buffer(tape);
1342 static int idetape_copy_stage_from_user(idetape_tape_t *tape,
1343 const char __user *buf, int n)
1345 struct idetape_bh *bh = tape->bh;
1351 printk(KERN_ERR "ide-tape: bh == NULL in %s\n",
1355 count = min((unsigned int)
1356 (bh->b_size - atomic_read(&bh->b_count)),
1358 if (copy_from_user(bh->b_data + atomic_read(&bh->b_count), buf,
1362 atomic_add(count, &bh->b_count);
1364 if (atomic_read(&bh->b_count) == bh->b_size) {
1367 atomic_set(&bh->b_count, 0);
1374 static int idetape_copy_stage_to_user(idetape_tape_t *tape, char __user *buf,
1377 struct idetape_bh *bh = tape->bh;
1383 printk(KERN_ERR "ide-tape: bh == NULL in %s\n",
1387 count = min(tape->b_count, n);
1388 if (copy_to_user(buf, tape->b_data, count))
1391 tape->b_data += count;
1392 tape->b_count -= count;
1394 if (!tape->b_count) {
1398 tape->b_data = bh->b_data;
1399 tape->b_count = atomic_read(&bh->b_count);
1406 static void idetape_init_merge_buffer(idetape_tape_t *tape)
1408 struct idetape_bh *bh = tape->merge_bh;
1409 tape->bh = tape->merge_bh;
1411 if (tape->chrdev_dir == IDETAPE_DIR_WRITE)
1412 atomic_set(&bh->b_count, 0);
1414 tape->b_data = bh->b_data;
1415 tape->b_count = atomic_read(&bh->b_count);
1420 * Write a filemark if write_filemark=1. Flush the device buffers without
1421 * writing a filemark otherwise.
1423 static void idetape_create_write_filemark_cmd(ide_drive_t *drive,
1424 struct ide_atapi_pc *pc, int write_filemark)
1426 idetape_init_pc(pc);
1427 pc->c[0] = WRITE_FILEMARKS;
1428 pc->c[4] = write_filemark;
1429 pc->flags |= PC_FLAG_WAIT_FOR_DSC;
1432 static void idetape_create_test_unit_ready_cmd(struct ide_atapi_pc *pc)
1434 idetape_init_pc(pc);
1435 pc->c[0] = TEST_UNIT_READY;
1439 * We add a special packet command request to the tail of the request queue, and
1440 * wait for it to be serviced. This is not to be called from within the request
1441 * handling part of the driver! We allocate here data on the stack and it is
1442 * valid until the request is finished. This is not the case for the bottom part
1443 * of the driver, where we are always leaving the functions to wait for an
1444 * interrupt or a timer event.
1446 * From the bottom part of the driver, we should allocate safe memory using
1447 * idetape_next_pc_storage() and ide_tape_next_rq_storage(), and add the request
1448 * to the request list without waiting for it to be serviced! In that case, we
1449 * usually use idetape_queue_pc_head().
1451 static int idetape_queue_pc_tail(ide_drive_t *drive, struct ide_atapi_pc *pc)
1453 struct ide_tape_obj *tape = drive->driver_data;
1457 rq = blk_get_request(drive->queue, READ, __GFP_WAIT);
1458 rq->cmd_type = REQ_TYPE_SPECIAL;
1459 rq->cmd[0] = REQ_IDETAPE_PC1;
1460 rq->buffer = (char *)pc;
1461 error = blk_execute_rq(drive->queue, tape->disk, rq, 0);
1462 blk_put_request(rq);
1466 static void idetape_create_load_unload_cmd(ide_drive_t *drive,
1467 struct ide_atapi_pc *pc, int cmd)
1469 idetape_init_pc(pc);
1470 pc->c[0] = START_STOP;
1472 pc->flags |= PC_FLAG_WAIT_FOR_DSC;
1475 static int idetape_wait_ready(ide_drive_t *drive, unsigned long timeout)
1477 idetape_tape_t *tape = drive->driver_data;
1478 struct ide_atapi_pc pc;
1479 int load_attempted = 0;
1481 /* Wait for the tape to become ready */
1482 set_bit(IDETAPE_FLAG_MEDIUM_PRESENT, &tape->flags);
1484 while (time_before(jiffies, timeout)) {
1485 idetape_create_test_unit_ready_cmd(&pc);
1486 if (!idetape_queue_pc_tail(drive, &pc))
1488 if ((tape->sense_key == 2 && tape->asc == 4 && tape->ascq == 2)
1489 || (tape->asc == 0x3A)) {
1493 idetape_create_load_unload_cmd(drive, &pc,
1494 IDETAPE_LU_LOAD_MASK);
1495 idetape_queue_pc_tail(drive, &pc);
1497 /* not about to be ready */
1498 } else if (!(tape->sense_key == 2 && tape->asc == 4 &&
1499 (tape->ascq == 1 || tape->ascq == 8)))
1506 static int idetape_flush_tape_buffers(ide_drive_t *drive)
1508 struct ide_atapi_pc pc;
1511 idetape_create_write_filemark_cmd(drive, &pc, 0);
1512 rc = idetape_queue_pc_tail(drive, &pc);
1515 idetape_wait_ready(drive, 60 * 5 * HZ);
1519 static void idetape_create_read_position_cmd(struct ide_atapi_pc *pc)
1521 idetape_init_pc(pc);
1522 pc->c[0] = READ_POSITION;
1526 static int idetape_read_position(ide_drive_t *drive)
1528 idetape_tape_t *tape = drive->driver_data;
1529 struct ide_atapi_pc pc;
1532 debug_log(DBG_PROCS, "Enter %s\n", __func__);
1534 idetape_create_read_position_cmd(&pc);
1535 if (idetape_queue_pc_tail(drive, &pc))
1537 position = tape->first_frame;
1541 static void idetape_create_locate_cmd(ide_drive_t *drive,
1542 struct ide_atapi_pc *pc,
1543 unsigned int block, u8 partition, int skip)
1545 idetape_init_pc(pc);
1546 pc->c[0] = POSITION_TO_ELEMENT;
1548 put_unaligned(cpu_to_be32(block), (unsigned int *) &pc->c[3]);
1549 pc->c[8] = partition;
1550 pc->flags |= PC_FLAG_WAIT_FOR_DSC;
1553 static int idetape_create_prevent_cmd(ide_drive_t *drive,
1554 struct ide_atapi_pc *pc, int prevent)
1556 idetape_tape_t *tape = drive->driver_data;
1558 /* device supports locking according to capabilities page */
1559 if (!(tape->caps[6] & 0x01))
1562 idetape_init_pc(pc);
1563 pc->c[0] = ALLOW_MEDIUM_REMOVAL;
1568 static void __ide_tape_discard_merge_buffer(ide_drive_t *drive)
1570 idetape_tape_t *tape = drive->driver_data;
1572 if (tape->chrdev_dir != IDETAPE_DIR_READ)
1575 clear_bit(IDETAPE_FLAG_FILEMARK, &tape->flags);
1576 tape->merge_bh_size = 0;
1577 if (tape->merge_bh != NULL) {
1578 ide_tape_kfree_buffer(tape);
1579 tape->merge_bh = NULL;
1582 tape->chrdev_dir = IDETAPE_DIR_NONE;
1586 * Position the tape to the requested block using the LOCATE packet command.
1587 * A READ POSITION command is then issued to check where we are positioned. Like
1588 * all higher level operations, we queue the commands at the tail of the request
1589 * queue and wait for their completion.
1591 static int idetape_position_tape(ide_drive_t *drive, unsigned int block,
1592 u8 partition, int skip)
1594 idetape_tape_t *tape = drive->driver_data;
1596 struct ide_atapi_pc pc;
1598 if (tape->chrdev_dir == IDETAPE_DIR_READ)
1599 __ide_tape_discard_merge_buffer(drive);
1600 idetape_wait_ready(drive, 60 * 5 * HZ);
1601 idetape_create_locate_cmd(drive, &pc, block, partition, skip);
1602 retval = idetape_queue_pc_tail(drive, &pc);
1606 idetape_create_read_position_cmd(&pc);
1607 return (idetape_queue_pc_tail(drive, &pc));
1610 static void ide_tape_discard_merge_buffer(ide_drive_t *drive,
1611 int restore_position)
1613 idetape_tape_t *tape = drive->driver_data;
1616 __ide_tape_discard_merge_buffer(drive);
1617 if (restore_position) {
1618 position = idetape_read_position(drive);
1619 seek = position > 0 ? position : 0;
1620 if (idetape_position_tape(drive, seek, 0, 0)) {
1621 printk(KERN_INFO "ide-tape: %s: position_tape failed in"
1622 " %s\n", tape->name, __func__);
1629 * Generate a read/write request for the block device interface and wait for it
1632 static int idetape_queue_rw_tail(ide_drive_t *drive, int cmd, int blocks,
1633 struct idetape_bh *bh)
1635 idetape_tape_t *tape = drive->driver_data;
1639 debug_log(DBG_SENSE, "%s: cmd=%d\n", __func__, cmd);
1641 rq = blk_get_request(drive->queue, READ, __GFP_WAIT);
1642 rq->cmd_type = REQ_TYPE_SPECIAL;
1644 rq->rq_disk = tape->disk;
1645 rq->special = (void *)bh;
1646 rq->sector = tape->first_frame;
1647 rq->nr_sectors = blocks;
1648 rq->current_nr_sectors = blocks;
1649 blk_execute_rq(drive->queue, tape->disk, rq, 0);
1651 errors = rq->errors;
1652 ret = tape->blk_size * (blocks - rq->current_nr_sectors);
1653 blk_put_request(rq);
1655 if ((cmd & (REQ_IDETAPE_READ | REQ_IDETAPE_WRITE)) == 0)
1659 idetape_init_merge_buffer(tape);
1660 if (errors == IDETAPE_ERROR_GENERAL)
1665 static void idetape_create_inquiry_cmd(struct ide_atapi_pc *pc)
1667 idetape_init_pc(pc);
1673 static void idetape_create_rewind_cmd(ide_drive_t *drive,
1674 struct ide_atapi_pc *pc)
1676 idetape_init_pc(pc);
1677 pc->c[0] = REZERO_UNIT;
1678 pc->flags |= PC_FLAG_WAIT_FOR_DSC;
1681 static void idetape_create_erase_cmd(struct ide_atapi_pc *pc)
1683 idetape_init_pc(pc);
1686 pc->flags |= PC_FLAG_WAIT_FOR_DSC;
1689 static void idetape_create_space_cmd(struct ide_atapi_pc *pc, int count, u8 cmd)
1691 idetape_init_pc(pc);
1693 put_unaligned(cpu_to_be32(count), (unsigned int *) &pc->c[1]);
1695 pc->flags |= PC_FLAG_WAIT_FOR_DSC;
1698 /* Queue up a character device originated write request. */
1699 static int idetape_add_chrdev_write_request(ide_drive_t *drive, int blocks)
1701 idetape_tape_t *tape = drive->driver_data;
1703 debug_log(DBG_CHRDEV, "Enter %s\n", __func__);
1705 return idetape_queue_rw_tail(drive, REQ_IDETAPE_WRITE,
1706 blocks, tape->merge_bh);
1709 static void ide_tape_flush_merge_buffer(ide_drive_t *drive)
1711 idetape_tape_t *tape = drive->driver_data;
1713 struct idetape_bh *bh;
1715 if (tape->chrdev_dir != IDETAPE_DIR_WRITE) {
1716 printk(KERN_ERR "ide-tape: bug: Trying to empty merge buffer"
1717 " but we are not writing.\n");
1720 if (tape->merge_bh_size > tape->buffer_size) {
1721 printk(KERN_ERR "ide-tape: bug: merge_buffer too big\n");
1722 tape->merge_bh_size = tape->buffer_size;
1724 if (tape->merge_bh_size) {
1725 blocks = tape->merge_bh_size / tape->blk_size;
1726 if (tape->merge_bh_size % tape->blk_size) {
1730 i = tape->blk_size - tape->merge_bh_size %
1732 bh = tape->bh->b_reqnext;
1734 atomic_set(&bh->b_count, 0);
1740 printk(KERN_INFO "ide-tape: bug,"
1744 min = min(i, (unsigned int)(bh->b_size -
1745 atomic_read(&bh->b_count)));
1746 memset(bh->b_data + atomic_read(&bh->b_count),
1748 atomic_add(min, &bh->b_count);
1753 (void) idetape_add_chrdev_write_request(drive, blocks);
1754 tape->merge_bh_size = 0;
1756 if (tape->merge_bh != NULL) {
1757 ide_tape_kfree_buffer(tape);
1758 tape->merge_bh = NULL;
1760 tape->chrdev_dir = IDETAPE_DIR_NONE;
1763 static int idetape_init_read(ide_drive_t *drive)
1765 idetape_tape_t *tape = drive->driver_data;
1768 /* Initialize read operation */
1769 if (tape->chrdev_dir != IDETAPE_DIR_READ) {
1770 if (tape->chrdev_dir == IDETAPE_DIR_WRITE) {
1771 ide_tape_flush_merge_buffer(drive);
1772 idetape_flush_tape_buffers(drive);
1774 if (tape->merge_bh || tape->merge_bh_size) {
1775 printk(KERN_ERR "ide-tape: merge_bh_size should be"
1777 tape->merge_bh_size = 0;
1779 tape->merge_bh = ide_tape_kmalloc_buffer(tape, 0, 0);
1780 if (!tape->merge_bh)
1782 tape->chrdev_dir = IDETAPE_DIR_READ;
1785 * Issue a read 0 command to ensure that DSC handshake is
1786 * switched from completion mode to buffer available mode.
1787 * No point in issuing this if DSC overlap isn't supported, some
1788 * drives (Seagate STT3401A) will return an error.
1790 if (drive->dsc_overlap) {
1791 bytes_read = idetape_queue_rw_tail(drive,
1792 REQ_IDETAPE_READ, 0,
1794 if (bytes_read < 0) {
1795 ide_tape_kfree_buffer(tape);
1796 tape->merge_bh = NULL;
1797 tape->chrdev_dir = IDETAPE_DIR_NONE;
1806 /* called from idetape_chrdev_read() to service a chrdev read request. */
1807 static int idetape_add_chrdev_read_request(ide_drive_t *drive, int blocks)
1809 idetape_tape_t *tape = drive->driver_data;
1811 debug_log(DBG_PROCS, "Enter %s, %d blocks\n", __func__, blocks);
1813 /* If we are at a filemark, return a read length of 0 */
1814 if (test_bit(IDETAPE_FLAG_FILEMARK, &tape->flags))
1817 idetape_init_read(drive);
1819 return idetape_queue_rw_tail(drive, REQ_IDETAPE_READ, blocks,
1823 static void idetape_pad_zeros(ide_drive_t *drive, int bcount)
1825 idetape_tape_t *tape = drive->driver_data;
1826 struct idetape_bh *bh;
1832 bh = tape->merge_bh;
1833 count = min(tape->buffer_size, bcount);
1835 blocks = count / tape->blk_size;
1837 atomic_set(&bh->b_count,
1838 min(count, (unsigned int)bh->b_size));
1839 memset(bh->b_data, 0, atomic_read(&bh->b_count));
1840 count -= atomic_read(&bh->b_count);
1843 idetape_queue_rw_tail(drive, REQ_IDETAPE_WRITE, blocks,
1849 * Rewinds the tape to the Beginning Of the current Partition (BOP). We
1850 * currently support only one partition.
1852 static int idetape_rewind_tape(ide_drive_t *drive)
1855 struct ide_atapi_pc pc;
1856 idetape_tape_t *tape;
1857 tape = drive->driver_data;
1859 debug_log(DBG_SENSE, "Enter %s\n", __func__);
1861 idetape_create_rewind_cmd(drive, &pc);
1862 retval = idetape_queue_pc_tail(drive, &pc);
1866 idetape_create_read_position_cmd(&pc);
1867 retval = idetape_queue_pc_tail(drive, &pc);
1873 /* mtio.h compatible commands should be issued to the chrdev interface. */
1874 static int idetape_blkdev_ioctl(ide_drive_t *drive, unsigned int cmd,
1877 idetape_tape_t *tape = drive->driver_data;
1878 void __user *argp = (void __user *)arg;
1880 struct idetape_config {
1881 int dsc_rw_frequency;
1882 int dsc_media_access_frequency;
1886 debug_log(DBG_PROCS, "Enter %s\n", __func__);
1890 if (copy_from_user(&config, argp, sizeof(config)))
1892 tape->best_dsc_rw_freq = config.dsc_rw_frequency;
1895 config.dsc_rw_frequency = (int) tape->best_dsc_rw_freq;
1896 config.nr_stages = 1;
1897 if (copy_to_user(argp, &config, sizeof(config)))
1906 static int idetape_space_over_filemarks(ide_drive_t *drive, short mt_op,
1909 idetape_tape_t *tape = drive->driver_data;
1910 struct ide_atapi_pc pc;
1911 int retval, count = 0;
1912 int sprev = !!(tape->caps[4] & 0x20);
1916 if (MTBSF == mt_op || MTBSFM == mt_op) {
1919 mt_count = -mt_count;
1922 if (tape->chrdev_dir == IDETAPE_DIR_READ) {
1923 tape->merge_bh_size = 0;
1924 if (test_and_clear_bit(IDETAPE_FLAG_FILEMARK, &tape->flags))
1926 ide_tape_discard_merge_buffer(drive, 0);
1932 idetape_create_space_cmd(&pc, mt_count - count,
1933 IDETAPE_SPACE_OVER_FILEMARK);
1934 return idetape_queue_pc_tail(drive, &pc);
1939 retval = idetape_space_over_filemarks(drive, MTFSF,
1943 count = (MTBSFM == mt_op ? 1 : -1);
1944 return idetape_space_over_filemarks(drive, MTFSF, count);
1946 printk(KERN_ERR "ide-tape: MTIO operation %d not supported\n",
1953 * Our character device read / write functions.
1955 * The tape is optimized to maximize throughput when it is transferring an
1956 * integral number of the "continuous transfer limit", which is a parameter of
1957 * the specific tape (26kB on my particular tape, 32kB for Onstream).
1959 * As of version 1.3 of the driver, the character device provides an abstract
1960 * continuous view of the media - any mix of block sizes (even 1 byte) on the
1961 * same backup/restore procedure is supported. The driver will internally
1962 * convert the requests to the recommended transfer unit, so that an unmatch
1963 * between the user's block size to the recommended size will only result in a
1964 * (slightly) increased driver overhead, but will no longer hit performance.
1965 * This is not applicable to Onstream.
1967 static ssize_t idetape_chrdev_read(struct file *file, char __user *buf,
1968 size_t count, loff_t *ppos)
1970 struct ide_tape_obj *tape = ide_tape_f(file);
1971 ide_drive_t *drive = tape->drive;
1972 ssize_t bytes_read, temp, actually_read = 0, rc;
1974 u16 ctl = *(u16 *)&tape->caps[12];
1976 debug_log(DBG_CHRDEV, "Enter %s, count %Zd\n", __func__, count);
1978 if (tape->chrdev_dir != IDETAPE_DIR_READ) {
1979 if (test_bit(IDETAPE_FLAG_DETECT_BS, &tape->flags))
1980 if (count > tape->blk_size &&
1981 (count % tape->blk_size) == 0)
1982 tape->user_bs_factor = count / tape->blk_size;
1984 rc = idetape_init_read(drive);
1989 if (tape->merge_bh_size) {
1990 actually_read = min((unsigned int)(tape->merge_bh_size),
1991 (unsigned int)count);
1992 if (idetape_copy_stage_to_user(tape, buf, actually_read))
1994 buf += actually_read;
1995 tape->merge_bh_size -= actually_read;
1996 count -= actually_read;
1998 while (count >= tape->buffer_size) {
1999 bytes_read = idetape_add_chrdev_read_request(drive, ctl);
2000 if (bytes_read <= 0)
2002 if (idetape_copy_stage_to_user(tape, buf, bytes_read))
2005 count -= bytes_read;
2006 actually_read += bytes_read;
2009 bytes_read = idetape_add_chrdev_read_request(drive, ctl);
2010 if (bytes_read <= 0)
2012 temp = min((unsigned long)count, (unsigned long)bytes_read);
2013 if (idetape_copy_stage_to_user(tape, buf, temp))
2015 actually_read += temp;
2016 tape->merge_bh_size = bytes_read-temp;
2019 if (!actually_read && test_bit(IDETAPE_FLAG_FILEMARK, &tape->flags)) {
2020 debug_log(DBG_SENSE, "%s: spacing over filemark\n", tape->name);
2022 idetape_space_over_filemarks(drive, MTFSF, 1);
2026 return ret ? ret : actually_read;
2029 static ssize_t idetape_chrdev_write(struct file *file, const char __user *buf,
2030 size_t count, loff_t *ppos)
2032 struct ide_tape_obj *tape = ide_tape_f(file);
2033 ide_drive_t *drive = tape->drive;
2034 ssize_t actually_written = 0;
2036 u16 ctl = *(u16 *)&tape->caps[12];
2038 /* The drive is write protected. */
2039 if (tape->write_prot)
2042 debug_log(DBG_CHRDEV, "Enter %s, count %Zd\n", __func__, count);
2044 /* Initialize write operation */
2045 if (tape->chrdev_dir != IDETAPE_DIR_WRITE) {
2046 if (tape->chrdev_dir == IDETAPE_DIR_READ)
2047 ide_tape_discard_merge_buffer(drive, 1);
2048 if (tape->merge_bh || tape->merge_bh_size) {
2049 printk(KERN_ERR "ide-tape: merge_bh_size "
2050 "should be 0 now\n");
2051 tape->merge_bh_size = 0;
2053 tape->merge_bh = ide_tape_kmalloc_buffer(tape, 0, 0);
2054 if (!tape->merge_bh)
2056 tape->chrdev_dir = IDETAPE_DIR_WRITE;
2057 idetape_init_merge_buffer(tape);
2060 * Issue a write 0 command to ensure that DSC handshake is
2061 * switched from completion mode to buffer available mode. No
2062 * point in issuing this if DSC overlap isn't supported, some
2063 * drives (Seagate STT3401A) will return an error.
2065 if (drive->dsc_overlap) {
2066 ssize_t retval = idetape_queue_rw_tail(drive,
2067 REQ_IDETAPE_WRITE, 0,
2070 ide_tape_kfree_buffer(tape);
2071 tape->merge_bh = NULL;
2072 tape->chrdev_dir = IDETAPE_DIR_NONE;
2079 if (tape->merge_bh_size) {
2080 if (tape->merge_bh_size >= tape->buffer_size) {
2081 printk(KERN_ERR "ide-tape: bug: merge buf too big\n");
2082 tape->merge_bh_size = 0;
2084 actually_written = min((unsigned int)
2085 (tape->buffer_size - tape->merge_bh_size),
2086 (unsigned int)count);
2087 if (idetape_copy_stage_from_user(tape, buf, actually_written))
2089 buf += actually_written;
2090 tape->merge_bh_size += actually_written;
2091 count -= actually_written;
2093 if (tape->merge_bh_size == tape->buffer_size) {
2095 tape->merge_bh_size = 0;
2096 retval = idetape_add_chrdev_write_request(drive, ctl);
2101 while (count >= tape->buffer_size) {
2103 if (idetape_copy_stage_from_user(tape, buf, tape->buffer_size))
2105 buf += tape->buffer_size;
2106 count -= tape->buffer_size;
2107 retval = idetape_add_chrdev_write_request(drive, ctl);
2108 actually_written += tape->buffer_size;
2113 actually_written += count;
2114 if (idetape_copy_stage_from_user(tape, buf, count))
2116 tape->merge_bh_size += count;
2118 return ret ? ret : actually_written;
2121 static int idetape_write_filemark(ide_drive_t *drive)
2123 struct ide_atapi_pc pc;
2125 /* Write a filemark */
2126 idetape_create_write_filemark_cmd(drive, &pc, 1);
2127 if (idetape_queue_pc_tail(drive, &pc)) {
2128 printk(KERN_ERR "ide-tape: Couldn't write a filemark\n");
2135 * Called from idetape_chrdev_ioctl when the general mtio MTIOCTOP ioctl is
2138 * Note: MTBSF and MTBSFM are not supported when the tape doesn't support
2139 * spacing over filemarks in the reverse direction. In this case, MTFSFM is also
2140 * usually not supported.
2142 * The following commands are currently not supported:
2144 * MTFSS, MTBSS, MTWSM, MTSETDENSITY, MTSETDRVBUFFER, MT_ST_BOOLEANS,
2145 * MT_ST_WRITE_THRESHOLD.
2147 static int idetape_mtioctop(ide_drive_t *drive, short mt_op, int mt_count)
2149 idetape_tape_t *tape = drive->driver_data;
2150 struct ide_atapi_pc pc;
2153 debug_log(DBG_ERR, "Handling MTIOCTOP ioctl: mt_op=%d, mt_count=%d\n",
2163 return idetape_space_over_filemarks(drive, mt_op, mt_count);
2170 if (tape->write_prot)
2172 ide_tape_discard_merge_buffer(drive, 1);
2173 for (i = 0; i < mt_count; i++) {
2174 retval = idetape_write_filemark(drive);
2180 ide_tape_discard_merge_buffer(drive, 0);
2181 if (idetape_rewind_tape(drive))
2185 ide_tape_discard_merge_buffer(drive, 0);
2186 idetape_create_load_unload_cmd(drive, &pc,
2187 IDETAPE_LU_LOAD_MASK);
2188 return idetape_queue_pc_tail(drive, &pc);
2192 * If door is locked, attempt to unlock before
2193 * attempting to eject.
2195 if (tape->door_locked) {
2196 if (idetape_create_prevent_cmd(drive, &pc, 0))
2197 if (!idetape_queue_pc_tail(drive, &pc))
2198 tape->door_locked = DOOR_UNLOCKED;
2200 ide_tape_discard_merge_buffer(drive, 0);
2201 idetape_create_load_unload_cmd(drive, &pc,
2202 !IDETAPE_LU_LOAD_MASK);
2203 retval = idetape_queue_pc_tail(drive, &pc);
2205 clear_bit(IDETAPE_FLAG_MEDIUM_PRESENT, &tape->flags);
2208 ide_tape_discard_merge_buffer(drive, 0);
2209 return idetape_flush_tape_buffers(drive);
2211 ide_tape_discard_merge_buffer(drive, 0);
2212 idetape_create_load_unload_cmd(drive, &pc,
2213 IDETAPE_LU_RETENSION_MASK | IDETAPE_LU_LOAD_MASK);
2214 return idetape_queue_pc_tail(drive, &pc);
2216 idetape_create_space_cmd(&pc, 0, IDETAPE_SPACE_TO_EOD);
2217 return idetape_queue_pc_tail(drive, &pc);
2219 (void)idetape_rewind_tape(drive);
2220 idetape_create_erase_cmd(&pc);
2221 return idetape_queue_pc_tail(drive, &pc);
2224 if (mt_count < tape->blk_size ||
2225 mt_count % tape->blk_size)
2227 tape->user_bs_factor = mt_count / tape->blk_size;
2228 clear_bit(IDETAPE_FLAG_DETECT_BS, &tape->flags);
2230 set_bit(IDETAPE_FLAG_DETECT_BS, &tape->flags);
2233 ide_tape_discard_merge_buffer(drive, 0);
2234 return idetape_position_tape(drive,
2235 mt_count * tape->user_bs_factor, tape->partition, 0);
2237 ide_tape_discard_merge_buffer(drive, 0);
2238 return idetape_position_tape(drive, 0, mt_count, 0);
2242 if (!idetape_create_prevent_cmd(drive, &pc, 1))
2244 retval = idetape_queue_pc_tail(drive, &pc);
2247 tape->door_locked = DOOR_EXPLICITLY_LOCKED;
2250 if (!idetape_create_prevent_cmd(drive, &pc, 0))
2252 retval = idetape_queue_pc_tail(drive, &pc);
2255 tape->door_locked = DOOR_UNLOCKED;
2258 printk(KERN_ERR "ide-tape: MTIO operation %d not supported\n",
2265 * Our character device ioctls. General mtio.h magnetic io commands are
2266 * supported here, and not in the corresponding block interface. Our own
2267 * ide-tape ioctls are supported on both interfaces.
2269 static int idetape_chrdev_ioctl(struct inode *inode, struct file *file,
2270 unsigned int cmd, unsigned long arg)
2272 struct ide_tape_obj *tape = ide_tape_f(file);
2273 ide_drive_t *drive = tape->drive;
2277 int block_offset = 0, position = tape->first_frame;
2278 void __user *argp = (void __user *)arg;
2280 debug_log(DBG_CHRDEV, "Enter %s, cmd=%u\n", __func__, cmd);
2282 if (tape->chrdev_dir == IDETAPE_DIR_WRITE) {
2283 ide_tape_flush_merge_buffer(drive);
2284 idetape_flush_tape_buffers(drive);
2286 if (cmd == MTIOCGET || cmd == MTIOCPOS) {
2287 block_offset = tape->merge_bh_size /
2288 (tape->blk_size * tape->user_bs_factor);
2289 position = idetape_read_position(drive);
2295 if (copy_from_user(&mtop, argp, sizeof(struct mtop)))
2297 return idetape_mtioctop(drive, mtop.mt_op, mtop.mt_count);
2299 memset(&mtget, 0, sizeof(struct mtget));
2300 mtget.mt_type = MT_ISSCSI2;
2301 mtget.mt_blkno = position / tape->user_bs_factor - block_offset;
2303 ((tape->blk_size * tape->user_bs_factor)
2304 << MT_ST_BLKSIZE_SHIFT) & MT_ST_BLKSIZE_MASK;
2306 if (tape->drv_write_prot)
2307 mtget.mt_gstat |= GMT_WR_PROT(0xffffffff);
2309 if (copy_to_user(argp, &mtget, sizeof(struct mtget)))
2313 mtpos.mt_blkno = position / tape->user_bs_factor - block_offset;
2314 if (copy_to_user(argp, &mtpos, sizeof(struct mtpos)))
2318 if (tape->chrdev_dir == IDETAPE_DIR_READ)
2319 ide_tape_discard_merge_buffer(drive, 1);
2320 return idetape_blkdev_ioctl(drive, cmd, arg);
2325 * Do a mode sense page 0 with block descriptor and if it succeeds set the tape
2326 * block size with the reported value.
2328 static void ide_tape_get_bsize_from_bdesc(ide_drive_t *drive)
2330 idetape_tape_t *tape = drive->driver_data;
2331 struct ide_atapi_pc pc;
2333 idetape_create_mode_sense_cmd(&pc, IDETAPE_BLOCK_DESCRIPTOR);
2334 if (idetape_queue_pc_tail(drive, &pc)) {
2335 printk(KERN_ERR "ide-tape: Can't get block descriptor\n");
2336 if (tape->blk_size == 0) {
2337 printk(KERN_WARNING "ide-tape: Cannot deal with zero "
2338 "block size, assuming 32k\n");
2339 tape->blk_size = 32768;
2343 tape->blk_size = (pc.buf[4 + 5] << 16) +
2344 (pc.buf[4 + 6] << 8) +
2346 tape->drv_write_prot = (pc.buf[2] & 0x80) >> 7;
2349 static int idetape_chrdev_open(struct inode *inode, struct file *filp)
2351 unsigned int minor = iminor(inode), i = minor & ~0xc0;
2353 idetape_tape_t *tape;
2354 struct ide_atapi_pc pc;
2357 if (i >= MAX_HWIFS * MAX_DRIVES)
2360 tape = ide_tape_chrdev_get(i);
2364 debug_log(DBG_CHRDEV, "Enter %s\n", __func__);
2367 * We really want to do nonseekable_open(inode, filp); here, but some
2368 * versions of tar incorrectly call lseek on tapes and bail out if that
2369 * fails. So we disallow pread() and pwrite(), but permit lseeks.
2371 filp->f_mode &= ~(FMODE_PREAD | FMODE_PWRITE);
2373 drive = tape->drive;
2375 filp->private_data = tape;
2377 if (test_and_set_bit(IDETAPE_FLAG_BUSY, &tape->flags)) {
2382 retval = idetape_wait_ready(drive, 60 * HZ);
2384 clear_bit(IDETAPE_FLAG_BUSY, &tape->flags);
2385 printk(KERN_ERR "ide-tape: %s: drive not ready\n", tape->name);
2389 idetape_read_position(drive);
2390 if (!test_bit(IDETAPE_FLAG_ADDRESS_VALID, &tape->flags))
2391 (void)idetape_rewind_tape(drive);
2393 /* Read block size and write protect status from drive. */
2394 ide_tape_get_bsize_from_bdesc(drive);
2396 /* Set write protect flag if device is opened as read-only. */
2397 if ((filp->f_flags & O_ACCMODE) == O_RDONLY)
2398 tape->write_prot = 1;
2400 tape->write_prot = tape->drv_write_prot;
2402 /* Make sure drive isn't write protected if user wants to write. */
2403 if (tape->write_prot) {
2404 if ((filp->f_flags & O_ACCMODE) == O_WRONLY ||
2405 (filp->f_flags & O_ACCMODE) == O_RDWR) {
2406 clear_bit(IDETAPE_FLAG_BUSY, &tape->flags);
2412 /* Lock the tape drive door so user can't eject. */
2413 if (tape->chrdev_dir == IDETAPE_DIR_NONE) {
2414 if (idetape_create_prevent_cmd(drive, &pc, 1)) {
2415 if (!idetape_queue_pc_tail(drive, &pc)) {
2416 if (tape->door_locked != DOOR_EXPLICITLY_LOCKED)
2417 tape->door_locked = DOOR_LOCKED;
2428 static void idetape_write_release(ide_drive_t *drive, unsigned int minor)
2430 idetape_tape_t *tape = drive->driver_data;
2432 ide_tape_flush_merge_buffer(drive);
2433 tape->merge_bh = ide_tape_kmalloc_buffer(tape, 1, 0);
2434 if (tape->merge_bh != NULL) {
2435 idetape_pad_zeros(drive, tape->blk_size *
2436 (tape->user_bs_factor - 1));
2437 ide_tape_kfree_buffer(tape);
2438 tape->merge_bh = NULL;
2440 idetape_write_filemark(drive);
2441 idetape_flush_tape_buffers(drive);
2442 idetape_flush_tape_buffers(drive);
2445 static int idetape_chrdev_release(struct inode *inode, struct file *filp)
2447 struct ide_tape_obj *tape = ide_tape_f(filp);
2448 ide_drive_t *drive = tape->drive;
2449 struct ide_atapi_pc pc;
2450 unsigned int minor = iminor(inode);
2453 tape = drive->driver_data;
2455 debug_log(DBG_CHRDEV, "Enter %s\n", __func__);
2457 if (tape->chrdev_dir == IDETAPE_DIR_WRITE)
2458 idetape_write_release(drive, minor);
2459 if (tape->chrdev_dir == IDETAPE_DIR_READ) {
2461 ide_tape_discard_merge_buffer(drive, 1);
2464 if (minor < 128 && test_bit(IDETAPE_FLAG_MEDIUM_PRESENT, &tape->flags))
2465 (void) idetape_rewind_tape(drive);
2466 if (tape->chrdev_dir == IDETAPE_DIR_NONE) {
2467 if (tape->door_locked == DOOR_LOCKED) {
2468 if (idetape_create_prevent_cmd(drive, &pc, 0)) {
2469 if (!idetape_queue_pc_tail(drive, &pc))
2470 tape->door_locked = DOOR_UNLOCKED;
2474 clear_bit(IDETAPE_FLAG_BUSY, &tape->flags);
2481 * check the contents of the ATAPI IDENTIFY command results. We return:
2483 * 1 - If the tape can be supported by us, based on the information we have so
2486 * 0 - If this tape driver is not currently supported by us.
2488 static int idetape_identify_device(ide_drive_t *drive)
2490 u8 gcw[2], protocol, device_type, removable, packet_size;
2492 if (drive->id_read == 0)
2495 *((unsigned short *) &gcw) = drive->id->config;
2497 protocol = (gcw[1] & 0xC0) >> 6;
2498 device_type = gcw[1] & 0x1F;
2499 removable = !!(gcw[0] & 0x80);
2500 packet_size = gcw[0] & 0x3;
2502 /* Check that we can support this device */
2504 printk(KERN_ERR "ide-tape: Protocol (0x%02x) is not ATAPI\n",
2506 else if (device_type != 1)
2507 printk(KERN_ERR "ide-tape: Device type (0x%02x) is not set "
2508 "to tape\n", device_type);
2509 else if (!removable)
2510 printk(KERN_ERR "ide-tape: The removable flag is not set\n");
2511 else if (packet_size != 0) {
2512 printk(KERN_ERR "ide-tape: Packet size (0x%02x) is not 12"
2513 " bytes\n", packet_size);
2519 static void idetape_get_inquiry_results(ide_drive_t *drive)
2521 idetape_tape_t *tape = drive->driver_data;
2522 struct ide_atapi_pc pc;
2523 char fw_rev[6], vendor_id[10], product_id[18];
2525 idetape_create_inquiry_cmd(&pc);
2526 if (idetape_queue_pc_tail(drive, &pc)) {
2527 printk(KERN_ERR "ide-tape: %s: can't get INQUIRY results\n",
2531 memcpy(vendor_id, &pc.buf[8], 8);
2532 memcpy(product_id, &pc.buf[16], 16);
2533 memcpy(fw_rev, &pc.buf[32], 4);
2535 ide_fixstring(vendor_id, 10, 0);
2536 ide_fixstring(product_id, 18, 0);
2537 ide_fixstring(fw_rev, 6, 0);
2539 printk(KERN_INFO "ide-tape: %s <-> %s: %s %s rev %s\n",
2540 drive->name, tape->name, vendor_id, product_id, fw_rev);
2544 * Ask the tape about its various parameters. In particular, we will adjust our
2545 * data transfer buffer size to the recommended value as returned by the tape.
2547 static void idetape_get_mode_sense_results(ide_drive_t *drive)
2549 idetape_tape_t *tape = drive->driver_data;
2550 struct ide_atapi_pc pc;
2552 u8 speed, max_speed;
2554 idetape_create_mode_sense_cmd(&pc, IDETAPE_CAPABILITIES_PAGE);
2555 if (idetape_queue_pc_tail(drive, &pc)) {
2556 printk(KERN_ERR "ide-tape: Can't get tape parameters - assuming"
2557 " some default values\n");
2558 tape->blk_size = 512;
2559 put_unaligned(52, (u16 *)&tape->caps[12]);
2560 put_unaligned(540, (u16 *)&tape->caps[14]);
2561 put_unaligned(6*52, (u16 *)&tape->caps[16]);
2564 caps = pc.buf + 4 + pc.buf[3];
2566 /* convert to host order and save for later use */
2567 speed = be16_to_cpu(*(u16 *)&caps[14]);
2568 max_speed = be16_to_cpu(*(u16 *)&caps[8]);
2570 put_unaligned(max_speed, (u16 *)&caps[8]);
2571 put_unaligned(be16_to_cpu(*(u16 *)&caps[12]), (u16 *)&caps[12]);
2572 put_unaligned(speed, (u16 *)&caps[14]);
2573 put_unaligned(be16_to_cpu(*(u16 *)&caps[16]), (u16 *)&caps[16]);
2576 printk(KERN_INFO "ide-tape: %s: invalid tape speed "
2577 "(assuming 650KB/sec)\n", drive->name);
2578 put_unaligned(650, (u16 *)&caps[14]);
2581 printk(KERN_INFO "ide-tape: %s: invalid max_speed "
2582 "(assuming 650KB/sec)\n", drive->name);
2583 put_unaligned(650, (u16 *)&caps[8]);
2586 memcpy(&tape->caps, caps, 20);
2588 tape->blk_size = 512;
2589 else if (caps[7] & 0x04)
2590 tape->blk_size = 1024;
2593 #ifdef CONFIG_IDE_PROC_FS
2594 static void idetape_add_settings(ide_drive_t *drive)
2596 idetape_tape_t *tape = drive->driver_data;
2598 ide_add_setting(drive, "buffer", SETTING_READ, TYPE_SHORT, 0, 0xffff,
2599 1, 2, (u16 *)&tape->caps[16], NULL);
2600 ide_add_setting(drive, "speed", SETTING_READ, TYPE_SHORT, 0, 0xffff,
2601 1, 1, (u16 *)&tape->caps[14], NULL);
2602 ide_add_setting(drive, "buffer_size", SETTING_READ, TYPE_INT, 0, 0xffff,
2603 1, 1024, &tape->buffer_size, NULL);
2604 ide_add_setting(drive, "tdsc", SETTING_RW, TYPE_INT, IDETAPE_DSC_RW_MIN,
2605 IDETAPE_DSC_RW_MAX, 1000, HZ, &tape->best_dsc_rw_freq,
2607 ide_add_setting(drive, "dsc_overlap", SETTING_RW, TYPE_BYTE, 0, 1, 1,
2608 1, &drive->dsc_overlap, NULL);
2609 ide_add_setting(drive, "avg_speed", SETTING_READ, TYPE_INT, 0, 0xffff,
2610 1, 1, &tape->avg_speed, NULL);
2611 ide_add_setting(drive, "debug_mask", SETTING_RW, TYPE_INT, 0, 0xffff, 1,
2612 1, &tape->debug_mask, NULL);
2615 static inline void idetape_add_settings(ide_drive_t *drive) { ; }
2619 * The function below is called to:
2621 * 1. Initialize our various state variables.
2622 * 2. Ask the tape for its capabilities.
2623 * 3. Allocate a buffer which will be used for data transfer. The buffer size
2624 * is chosen based on the recommendation which we received in step 2.
2626 * Note that at this point ide.c already assigned us an irq, so that we can
2627 * queue requests here and wait for their completion.
2629 static void idetape_setup(ide_drive_t *drive, idetape_tape_t *tape, int minor)
2635 u16 *ctl = (u16 *)&tape->caps[12];
2637 spin_lock_init(&tape->lock);
2638 drive->dsc_overlap = 1;
2639 if (drive->hwif->host_flags & IDE_HFLAG_NO_DSC) {
2640 printk(KERN_INFO "ide-tape: %s: disabling DSC overlap\n",
2642 drive->dsc_overlap = 0;
2644 /* Seagate Travan drives do not support DSC overlap. */
2645 if (strstr(drive->id->model, "Seagate STT3401"))
2646 drive->dsc_overlap = 0;
2647 tape->minor = minor;
2648 tape->name[0] = 'h';
2649 tape->name[1] = 't';
2650 tape->name[2] = '0' + minor;
2651 tape->chrdev_dir = IDETAPE_DIR_NONE;
2652 tape->pc = tape->pc_stack;
2653 *((unsigned short *) &gcw) = drive->id->config;
2655 /* Command packet DRQ type */
2656 if (((gcw[0] & 0x60) >> 5) == 1)
2657 set_bit(IDETAPE_FLAG_DRQ_INTERRUPT, &tape->flags);
2659 idetape_get_inquiry_results(drive);
2660 idetape_get_mode_sense_results(drive);
2661 ide_tape_get_bsize_from_bdesc(drive);
2662 tape->user_bs_factor = 1;
2663 tape->buffer_size = *ctl * tape->blk_size;
2664 while (tape->buffer_size > 0xffff) {
2665 printk(KERN_NOTICE "ide-tape: decreasing stage size\n");
2667 tape->buffer_size = *ctl * tape->blk_size;
2669 buffer_size = tape->buffer_size;
2670 tape->pages_per_buffer = buffer_size / PAGE_SIZE;
2671 if (buffer_size % PAGE_SIZE) {
2672 tape->pages_per_buffer++;
2673 tape->excess_bh_size = PAGE_SIZE - buffer_size % PAGE_SIZE;
2676 /* select the "best" DSC read/write polling freq */
2677 speed = max(*(u16 *)&tape->caps[14], *(u16 *)&tape->caps[8]);
2679 t = (IDETAPE_FIFO_THRESHOLD * tape->buffer_size * HZ) / (speed * 1000);
2682 * Ensure that the number we got makes sense; limit it within
2683 * IDETAPE_DSC_RW_MIN and IDETAPE_DSC_RW_MAX.
2685 tape->best_dsc_rw_freq = clamp_t(unsigned long, t, IDETAPE_DSC_RW_MIN,
2686 IDETAPE_DSC_RW_MAX);
2687 printk(KERN_INFO "ide-tape: %s <-> %s: %dKBps, %d*%dkB buffer, "
2689 drive->name, tape->name, *(u16 *)&tape->caps[14],
2690 (*(u16 *)&tape->caps[16] * 512) / tape->buffer_size,
2691 tape->buffer_size / 1024,
2692 tape->best_dsc_rw_freq * 1000 / HZ,
2693 drive->using_dma ? ", DMA":"");
2695 idetape_add_settings(drive);
2698 static void ide_tape_remove(ide_drive_t *drive)
2700 idetape_tape_t *tape = drive->driver_data;
2702 ide_proc_unregister_driver(drive, tape->driver);
2704 ide_unregister_region(tape->disk);
2709 static void ide_tape_release(struct kref *kref)
2711 struct ide_tape_obj *tape = to_ide_tape(kref);
2712 ide_drive_t *drive = tape->drive;
2713 struct gendisk *g = tape->disk;
2715 BUG_ON(tape->merge_bh_size);
2717 drive->dsc_overlap = 0;
2718 drive->driver_data = NULL;
2719 device_destroy(idetape_sysfs_class, MKDEV(IDETAPE_MAJOR, tape->minor));
2720 device_destroy(idetape_sysfs_class,
2721 MKDEV(IDETAPE_MAJOR, tape->minor + 128));
2722 idetape_devs[tape->minor] = NULL;
2723 g->private_data = NULL;
2728 #ifdef CONFIG_IDE_PROC_FS
2729 static int proc_idetape_read_name
2730 (char *page, char **start, off_t off, int count, int *eof, void *data)
2732 ide_drive_t *drive = (ide_drive_t *) data;
2733 idetape_tape_t *tape = drive->driver_data;
2737 len = sprintf(out, "%s\n", tape->name);
2738 PROC_IDE_READ_RETURN(page, start, off, count, eof, len);
2741 static ide_proc_entry_t idetape_proc[] = {
2742 { "capacity", S_IFREG|S_IRUGO, proc_ide_read_capacity, NULL },
2743 { "name", S_IFREG|S_IRUGO, proc_idetape_read_name, NULL },
2744 { NULL, 0, NULL, NULL }
2748 static int ide_tape_probe(ide_drive_t *);
2750 static ide_driver_t idetape_driver = {
2752 .owner = THIS_MODULE,
2754 .bus = &ide_bus_type,
2756 .probe = ide_tape_probe,
2757 .remove = ide_tape_remove,
2758 .version = IDETAPE_VERSION,
2760 .supports_dsc_overlap = 1,
2761 .do_request = idetape_do_request,
2762 .end_request = idetape_end_request,
2763 .error = __ide_error,
2764 .abort = __ide_abort,
2765 #ifdef CONFIG_IDE_PROC_FS
2766 .proc = idetape_proc,
2770 /* Our character device supporting functions, passed to register_chrdev. */
2771 static const struct file_operations idetape_fops = {
2772 .owner = THIS_MODULE,
2773 .read = idetape_chrdev_read,
2774 .write = idetape_chrdev_write,
2775 .ioctl = idetape_chrdev_ioctl,
2776 .open = idetape_chrdev_open,
2777 .release = idetape_chrdev_release,
2780 static int idetape_open(struct inode *inode, struct file *filp)
2782 struct gendisk *disk = inode->i_bdev->bd_disk;
2783 struct ide_tape_obj *tape;
2785 tape = ide_tape_get(disk);
2792 static int idetape_release(struct inode *inode, struct file *filp)
2794 struct gendisk *disk = inode->i_bdev->bd_disk;
2795 struct ide_tape_obj *tape = ide_tape_g(disk);
2802 static int idetape_ioctl(struct inode *inode, struct file *file,
2803 unsigned int cmd, unsigned long arg)
2805 struct block_device *bdev = inode->i_bdev;
2806 struct ide_tape_obj *tape = ide_tape_g(bdev->bd_disk);
2807 ide_drive_t *drive = tape->drive;
2808 int err = generic_ide_ioctl(drive, file, bdev, cmd, arg);
2810 err = idetape_blkdev_ioctl(drive, cmd, arg);
2814 static struct block_device_operations idetape_block_ops = {
2815 .owner = THIS_MODULE,
2816 .open = idetape_open,
2817 .release = idetape_release,
2818 .ioctl = idetape_ioctl,
2821 static int ide_tape_probe(ide_drive_t *drive)
2823 idetape_tape_t *tape;
2827 if (!strstr("ide-tape", drive->driver_req))
2829 if (!drive->present)
2831 if (drive->media != ide_tape)
2833 if (!idetape_identify_device(drive)) {
2834 printk(KERN_ERR "ide-tape: %s: not supported by this version of"
2835 " the driver\n", drive->name);
2839 printk(KERN_INFO "ide-tape: passing drive %s to ide-scsi"
2840 " emulation.\n", drive->name);
2843 tape = kzalloc(sizeof(idetape_tape_t), GFP_KERNEL);
2845 printk(KERN_ERR "ide-tape: %s: Can't allocate a tape struct\n",
2850 g = alloc_disk(1 << PARTN_BITS);
2854 ide_init_disk(g, drive);
2856 ide_proc_register_driver(drive, &idetape_driver);
2858 kref_init(&tape->kref);
2860 tape->drive = drive;
2861 tape->driver = &idetape_driver;
2864 g->private_data = &tape->driver;
2866 drive->driver_data = tape;
2868 mutex_lock(&idetape_ref_mutex);
2869 for (minor = 0; idetape_devs[minor]; minor++)
2871 idetape_devs[minor] = tape;
2872 mutex_unlock(&idetape_ref_mutex);
2874 idetape_setup(drive, tape, minor);
2876 device_create(idetape_sysfs_class, &drive->gendev,
2877 MKDEV(IDETAPE_MAJOR, minor), "%s", tape->name);
2878 device_create(idetape_sysfs_class, &drive->gendev,
2879 MKDEV(IDETAPE_MAJOR, minor + 128), "n%s", tape->name);
2881 g->fops = &idetape_block_ops;
2882 ide_register_region(g);
2892 static void __exit idetape_exit(void)
2894 driver_unregister(&idetape_driver.gen_driver);
2895 class_destroy(idetape_sysfs_class);
2896 unregister_chrdev(IDETAPE_MAJOR, "ht");
2899 static int __init idetape_init(void)
2902 idetape_sysfs_class = class_create(THIS_MODULE, "ide_tape");
2903 if (IS_ERR(idetape_sysfs_class)) {
2904 idetape_sysfs_class = NULL;
2905 printk(KERN_ERR "Unable to create sysfs class for ide tapes\n");
2910 if (register_chrdev(IDETAPE_MAJOR, "ht", &idetape_fops)) {
2911 printk(KERN_ERR "ide-tape: Failed to register chrdev"
2914 goto out_free_class;
2917 error = driver_register(&idetape_driver.gen_driver);
2919 goto out_free_driver;
2924 driver_unregister(&idetape_driver.gen_driver);
2926 class_destroy(idetape_sysfs_class);
2931 MODULE_ALIAS("ide:*m-tape*");
2932 module_init(idetape_init);
2933 module_exit(idetape_exit);
2934 MODULE_ALIAS_CHARDEV_MAJOR(IDETAPE_MAJOR);
2935 MODULE_DESCRIPTION("ATAPI Streaming TAPE Driver");
2936 MODULE_LICENSE("GPL");